Electronic one-dimensional (1D) and two-dimensional (2D) imaging systems are in wide use. Examples of these include a 1D array of detectors for scanning images and a digital camera consisting of a 2D array of detectors. These detectors come in wide variety and employ many different read techniques. Typical features of these popular imaging systems are:    (a) A number of discrete detectors are used to sample 1D or 2D information.    (b) Higher resolution (as defined by pixels per unit length) is obtained by physically increasing the number of detector elements. For example, a 2D image formed by the optical imaging system may be collected using a CMOS-based imaging array. Higher the number of detector elements in each dimension, better the quality of the image.    (c) Higher resolution requires manufacturing each detector in close proximity to the other. A typical high-resolution CCD or a CMOS camera in the visible part of the electromagnetic spectrum may have a pixel size of 6-10 μm or a resolution of approximately 100 lines/mm. In contrast, a good photographic film provides a resolution of 1000-3000 lines/mm.    (d) In the visible region, silicon-based detectors work adequately and with good quantum efficiency. The cost of the focal plane arrays have fallen dramatically in recent times. But outside the visible region of the electromagnetic spectrum, novel and often exotic materials are required to form detectors and focal plane arrays. Factors such as yield, manufacturability, uniformity, or compatibility of these detector arrays with read-out electronics limits either the size of arrays or makes them very expensive compared to the Silicon-based detectors. For example, a 1000 by 1000 array of silicon detectors (as in a typical Mega-pixel digital camera) costs less than $10 to manufacture—the entire camera can be purchased for less than $100. But an array of 256 by 256 pixels sensitive to 1.3-1.5 μm region of the electromagnetic spectrum can cost upwards of $1000, with the camera itself costing tens of thousands of dollars. Other exotic/special materials for detectors include Mercury-Cadmium-Telluride system (3-10 μm), PbS (2-5 μm), PtSi (8-12 μm), LiTaO2 (as pyroelectric element), scintillators for UV and X-ray etc.    (e) In many cases, the imaging array needs to be cooled to reduce noise. This is particularly true in the infrared portion of the spectrum since the photon energy becomes comparable the energy of the thermal fluctuations at room temperature. Bigger detector arrays require more expensive cooling equipment as well as uniform cooling across the array.    (f) In many regions of the electromagnetic spectrum, imaging detectors are plagued by complex manufacturing steps, exotic materials, difficult or tedious calibration of individual pixels, long testing times, and number of dead pixels. These are some of the difficulties that keep the cost of imaging high.    (g) Most of the detector arrays are made on a plane substrate forcing optical designers to design imaging systems that have a planar imaging surface.